Airborne microplastics (MPs) are increasingly recognized as atmospheric pollutants with potential implications for human exposure; however, their occurrence, temporal variability, and associations with urban particulate matter remain poorly understood. This study investigated MPs associated with PM₁₀ in central Los Angeles across two seasonal sampling campaigns by integrating MP abundance, morphology, size distribution, PM₁₀ chemical composition, and meteorological observations. MPs were detected in all samples, with concentrations ranging from 2.2-4.0 MP/m³ during the cool-season campaign and 2.2-3.4 MP/m³ during the warm-season campaign. Fibers remained the dominant morphology, while particles <100 µm, particularly the 5-50 µm and 50-100 µm fractions, consistently dominated the airborne MP population. Strong positive correlations (generally ρ ≥ 0.79) were observed between total MP concentrations and major crustal (Fe, Si, Mn, Ca, Al, and Mg), traffic-related (Ba, Cu, and Ni), and carbonaceous (OC and EC) tracers, indicating that MPs are closely associated with urban particulate mixtures influenced by resuspension and non-tailpipe traffic emissions. In contrast, short-term meteorological variability showed no consistent relationship with MP concentrations. These findings indicate that airborne MPs are a persistent component of the urban PM10 mixture rather than isolated contaminants, and provide new insight into their sources and behavior in densely populated urban environments.